body {
  padding: 300px;
}
body .menu {
  width: 90px ;
  height: 100vh;
  position: relative;
}
body .menu:hover .btn {
  cursor: default;
  border-bottom: solid 1px white;
}
body .menu:hover .list {
  display: block;
}
body .menu .btn {
  border: solid 1px gray;
  width: 90px;
  height: 30px;
}
body .menu .list {
  z-index: -1;
  width: 170px;
  border: solid 1px gray;
  position: absolute;
  right: 0;
  top: 29px;
  display: flex;
  flex-wrap: wrap;
  padding: 10px;
  display: none;
}
body .menu .list span {
  font-weight: bold;
}
body .menu .list .list-menu {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
}
body .menu .list .list-menu a {
  text-decoration: none;
  font-size: 14px;
  color: gray;
}
